Ethanol inhibits cell adhesion mediated by the L1 cell adhesion molecule in neural cells and in fibroblasts ransfected with human L1. Because the brains of children with L1 mutations resemble those of children with tal alcohol syndrome, it is possible that inhibition of L1-mediated cell adhesion contributes to the eratogenic effects of ETOH. Structure activity analysis of a series of straight and branch-chain alcohols demonstrates remarkable structural specificity for alcohol inhibition of cell-cell adhesion. Moreover, we have dentified a series of compounds that antagonize the effects of ethanol on L1-mediated cell-cell adhesion, on BMP morphogenesis in cultured neural cells, and on the development of mouse whole embryo cultures. The underlying hypothesis of this proposal is that compounds that antagonize ethanol inhibition of L1-mediated cell-cell adhesion will also prevent ethanol teratogenesis. The proposed research has three specific aims: 1. To identify the structural determinants of alcohols and related compounds that are required for inhibition of cell-cell adhesion in L1-expressing cells and for antagonism of this inhibition; 2. To determine the mechanism(s) by which ethanol inhibits L1 adhesion and induces apoptotic cell death in neurons; 3. To characterize regions of L1 that are necessary for alcohol inhibition and for antagonism of ethanol inhibition; 4. To evaluate selected ethanol antagonists for their ability to prevent the teratogenic effects of ethanol in mouse whole embryo culture and during early embryogenesis in C57BI/J6 mice. Techniques employed in these studies will include mammalian cell transfection, cell-aggregation assays, mutagenesis of the L1 molecule, mousewhole embryo culture, and macroscopic and microscopic analysis of mice exposed to ethanol in utero. These experiments may lead to a better understanding of how ethanol interacts with neura proteins and may reveal mechanisms whereby ethanol causes birth defects. A major goal of the proposed research is to identify compounds that reduce the teratogenic effects of ethanol. PERFORMANCE SITE(S) (organization, city, state) Harvard Medical School,VA Boston Healthcare System, West Roxbury, MA Center for Alcohol Studies, University of North Carolina, Chapel Hill, NC KEY PERSONNEL. See instructions. Use continuation pages as needed to provide the required information in the format shown below. Start with Principal Investigator. List all other key personnel in alphabetical order, last name first. Name Organization Role on Project Michael E. Charness, M.D. Harvard Medical School PI Shailendra Kumar, Ph.D. Harvard Medical School Investigator Xiaowei Dou, Ph.D.i Harvard Medical School Postdoctoral Fellow Kathleen Sulik, Ph.D. University of North Carolina PI subcontract Shao-Yu Chen, Ph.D. University of North Carolina Investigator Zhong Lu University of North Carolina Postdoctoral Fellow Disclosure Permission Statement. Applicable to SBIR/STTR Only. Seeinstructions. [X] Yes I I No PHS 398 (Rev. 05/01) Page 2 Number pages consecutively at the bottom throughout Form Page 2 the application. Do not use suffixes such as 2a, 2b. Principal Investigator/Program Director (Last, First, Middle): ChameSS, Michael E. The name of the principal investigator/program director must be provided at the top of each printed page and each continuation page. RESEARCH GRANT TABLE OF CONTENTS Face Page Description,